HardRock® Multi-Fix (DD)
Designed for warm flat roofs, ROCKWOOL HardRock Multi-Fix (DD) is a high density, non-combustible thermal insulation board which has also been tested for acoustic applications and fire resistance.
ROCKWOOL HardRock Multi-Fix (DD) has been proven to improve the ability of lightweight flat roof systems to control both noise ingress and egress through the building envelope.
Suitable for areas subject to pedestrian traffic and frequent maintenance, the boards are compatible with all roof covering types, including torch-on, pour-and-roll, single-ply, EPDM, liquid applied and green roofs.
Specification
| NBS Clause | Length (mm) | Width (mm) | *Approved thickness range (mm) |
J21-425 J31 – 334 J41 – 425 J42 – 425 | 1200 | 1000 | 60 – 185 |
*Thickness options may be subject to a minimum production volume. Speak to the specification team for guidance.
Standards and Certification
| Product standards | BS EN 13162, ISO 14001 |
| CE Marking | CE Marked |
| BBA Approved | Certificate 21/5878 |
| LPCB Certified (LPS 1181: Part 1) | Certificate 022g |
Technical Properties
| Reaction to fire (Euroclass) | A2-s1,d0 (BS EN 13501-1) |
| Fire resistance | Up to 120 minutes |
| Thermal conductivity | 0.039 W/mK |
| Water vapour resistance | 5.9 MNs/gm |
Thermal Performance
HardRock Underlay (DD) (mm) | HardRock Multi-Fix (DD) (mm) | Single ply membrane U-value (W/m2K) | Bitumen (2-layer felt) U-value (W/m2K) |
| 150 | 60 | 0.18 | 0.18 |
| 150 | 85 | 0.16 | 0.16 |
| 150 | 105 | 0.15 | 0.15 |
Acoustic Performance
Insulation layer 1 (mm) | Insulation layer 2 (mm) | Airborne reduction (dB) | Rain intensity (dB) | Airborne reduction (dB) | Rain intensity (dB) |
| 150 | 60 | Rw 44 | LIA 48.7 | Rw 45 | LIA 47.5 |
| 150 | 85 | Rw 45 | LIA 47.8 | Rw 46 | LIA 46.7 |
| 150 | 105 | Rw 46 | LIA 47.1 | Rw 47 | LIA 46.1 |
Based on D60 profiled steel deck.
CAD Drawings
Download CAD Drawings here
